Table 1. Reference data on optical elements of the imaging system.

Item	Model	Reference for spectrum
1. Light source	FEI Polychrome V	on request from FEI-Munich
2. Excitation transmittance filter	Chroma 69008x	www.chroma.com
3. Dichroic mirror	Chroma 69008bs	www.chroma.com
4. Detector	PCO Sensicam VGA	www.pco.de
5. Emission transmittance filter	Chroma 69008m	www.chroma.com
6. Objective	Olympus UAPO 40XOI3/340	on request from Olympus